“Stiff.” “Spook.” “Bonk.” It’s interesting how so many of the books by Mary Roach — the wonderfully offbeat writer whose nonfiction work focuses on fascinating and humorous taboos related to science — have a primary title that is short, sweet, to the point. Sure, the subtitle is happy to add more detail — “Stiff’s” is “The Curious Lives of Human Cadavers,” “Spook’s” is “Science Tackles the Afterlife”— but their primary names are monosyllabic and blunt.

Mary Roach, photo copyright Chris Hardy Photography

“Actually, it wasn’t an intentional marketing strategy,” Roach said in an interview with Toledo Free Press. “‘Stiff’ was just the first one, and ‘Spook’ was the second one, and then it became a pattern, so we stuck with it. Although ‘Packing for Mars,’ we couldn’t come up with anything. Nothing. Everybody tried.

“Also, I have a tendency to not remember the names of — right now, I’m reading a book entitled … something like, ‘Let the World Spin?’ If it’s more than two words, I can’t remember it.”

Roach’s newest title fits right into her canon in almost every way. After spending tomes dissecting such delightfully gross subject matter as what happens to dead bodies and the science of sex, a cheerful tour of the digestive tract — from mouth to anus and everything in between — seems the perfect subject matter. The main title is, as usual, wonderfully direct: “Gulp.”

Now available in paperback, “Gulp” (subtitled “Adventures on the Alimentary Canal”) is another wonderfully entertaining read from Roach, who has carved out a niche as one of the most interesting science writers out there — a fascinating accolade, seeing as how she never intended for this to be her regular beat.

“It was not really a conscious choice. I seem to be fairly passive in my decision making,” Roach said with a chuckle. “I ended up writing for many years for a magazine called ‘Hippocrates,’ which ended up changing names, and also ‘Discover.’ So those are two magazines that dealt with science and medicine and the human body, and I wrote for them for about 10 years or so. So that’s kind of how it happened. It wasn’t something I set out to do.”

Arguably, though, Roach’s relative naiveté toward her subjects works in her favor. In each of her works, she brings a sense of enthusiastic discovery to every fact she discusses, no matter if she’s covering outer or inner space.

“I’m approaching a topic as a near-total ignoramus,” Roach said. “I have this kind of naive wonder and awe at the things that I’m learning about the human body. I’ll go, ‘Oh, that’s why when you get up in the morning you have to pee all of a sudden! It’s the stretch receptors, and it’s the fluid at the bottom of the organ, and … wow, that’s how it works!’ Where if you were a medical professional, you would have learned that a long time ago, it wouldn’t really be of interest to you.”

Certainly one of Roach’s trademarks is her humor. In each book, she finds ways to bring her audience along for a discussion of topics most of us would have difficulty talking about in polite company — bacteria, corpses, feces, disease. And among the ways she gets around our natural distaste for such subjects is among the most basic: She makes them funny as hell.

“I’m definitely choosing subject matter that will enable me to do that, because it’s more fun for me, and I assume if it’s more fun for me to write it, it’ll be fun to read it,” Roach said.

Not that everything is a laughing matter.

“There’s been times I’ve wanted to explore a subject where there really wasn’t much room for humor, and in ‘Stiff,’ there was a chapter on the forensics of plane crash victims, and how the bodies can be used to understand what happened on the plane,” she said. “A really dark topic. One of the examples was TWA Flight 800, and I thought, ‘Those people could read this.’ And it’s not funny. So that’s not a funny chapter. Sometimes it’s impossible, or inappropriate.”

No matter what her topic, though, Roach continues to find new ways to make her off-center subject matter both wildly interesting and engaging.

“I think that’s part of what draws me to these topics — the fact that it is a taboo and that people turn away from it, so for that reason, everything is going to be surprising and fresh. Because nobody wants to really think about it or read about it, and then someone like me steps in and goes, ‘Wait a minute. It’s actually really interesting and weird, and you need to read this.’

“People kind of appreciate that you’re just laying it out there. People want to talk about these things, they just don’t quite know how. So you’re giving them an example, which is just plunge in and say it. There’s nothing to be ashamed of. It’s all kind of miraculous physiology, in my opinion.”